Shock absorbing means



Sept. 13, 1949. Q. FRAZIER I SHOCK ABSORBING MEANS Filed Nov. 25, 1945 l N VEN TOR.

Patented Sept. 13, 1949 SHOCK ABSOBLBING Qu ntin. Fr r,

signor to the United St West Long Branch, N. J., asates of Americans represented by the Secretary of War Application N vember 23, 19 5, Se ial N 630,513

6 Claims, (01. 248-358) (Granted u d r h t of Ma ch amended April 30, 1928; 371) 0.. 757) The invention described herein may be manor featured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

The present invention relates to shock absorblng means.

With the tremendous use of highly sensitive electronic and electrical devices, a need has arisen for suitable mounting means to sustain such an.- parat-us or components thereof and protect them from vibrations and shocks incident to transportation, to vehicular use and the like. In order to completely protect such equipment, the mountin; means should be such as to have compliance and shock absorbing qualities in all directions, so as to isolate the equipment from shock in all directions, irrespective of the position in which the equipment is sustained.

1t is therefore an object of the present inventlon to provide means for shock mounting apparatus which allow movements thereof in all directions and which absorb shocks implicit in such universal movements.

' It is a, further object of the present invention to provide means for mounting sensitive equipment which allow its center of gravity to be so positioned as to eliminate or at least minimize harmful effects due to shock.

' It is a further object to provide a shock absorbing carrying case for delicate instruments and the like.

These and other objects and advantages of the present invention, which will be better understood as the detailed description thereof pro grosses, are obtained in the following manner.

There are provided preferably at least three points springs, each of which is made of an elongated plate of springy metal rolled into a spiral form and has an axially positioned rod extending through, and secured to, its innermost turn to which a load may be secured. Each spring is held in a suitable spring housing which secures the outer turn thereof. A preferred embodiment,

as illustrated in the drawings annexed hereto,

comprises a case, into which the housings of four of such volute springs are secured, and a rigid framework, carried by rods ex d n a ly through said four springs, to which a load, such as an. electrical instrument m be sec r d.

Preferably the center of gravity of the load and the framework is in a plane which extends throu h the midooints of. the ou sprin s.

:It will be understood th t the p s nt application is not to be. lim ted t an par icula numbe! of prings, it bolus Possible t shock mount a load upon a single spring as described above, in which event the load Should be so distributed about the axially disposed shaft, or so counterbalanced, that the center of gravi y o h nti e load carried by the spring located at the midpoint of said spring.

in the accompanyin spe ifi a n there is d scribed, and in the annexed drawin s sh wn, wh t at present is considered preferred m odim n s of the present invention. It is however to be understood that said invention is n t limited to aid embodiments inasmuch as changes therein may be made without the xercise of inv ntion nd within the true spirit and scope of the claims hereto appended,

n h drawin s,

Figure l is an isometric view, partly broken away, of an electrical in rum n sh mo n e in a carrying ase mb dying h present invention:

Figure 2 is ievational view p y t oned, of one Of the shock mounts and associated parts of Figure 1; and

Figure 3 is an elevational view of a modified form of shock mount- Referring now par i ularl o Fig r s 1 and 2 of the drawin s, the. mbodiment of the p ent invention there illustrated comprises a rectangular case I I into each of the four corners of which is secured a shock mount l3. Each such shock mount 13 includes a spring I5 which is made up of a length of flat spring steel stock coiled into a volute shape. The four said springs l5 are disposed so that their axes are mutually parallel and the midpoints of a l four springs lie in a single plane normal to said axes, The outer layer o each sprin 5 is encompassed and rigidly held within. a snu l fitting spring housing H whic comprises a tubular s ev l9 provided with w rin s suitably secur d pectively withi the opposite ends of said l ac u h spring h usin I also includes two metal straps 23, welded orotherwise securely fastened thereto at right angles to each oth r, by which said nous ins is secured to the Walls of the case I as by bolts 25.

An elongated threaded rod 2-1 extends through the axis of each of said springs l5 and is held risidlr eoured o th inner urn t er f y w sh ers and nuts 29 positioned both above and below each spring.-

A rigid rectangular upper frame 3|, pierced by four corner holes receivable to the rods 21, is positioned above the four springs l5 and spaced a um ien istance therefrom so as not to i terfour springs I5. An electrical instrument 3! is rigidly fastened to the'upper and lower frames 3|, 35 as by the bolts 33, the said ins'trument'being so positioned that its centerof gravity is in v the plane aforementioned which passes through the midpoints of the four springs I5.

Threadably secured to each end of each of tjhe rods 21 is a snubber plate 4I' prov'ided with a flat surface 43, normal to the rod axis, atits extremity. A snubber pad 45, of soft resilient material such as sponge rubber, is; attached to the 4 three spaced-springs disposed with their axes interior of the case I I at each of *the four corners of the top-and bottom walls thereof. Said snuhber pads 45 are alignedwith-the rods 21 and are spaced from the snubber plates 4|. I

In the use of the device just described, the

shock mounts I3 will allow the ins'trum'ent 311to move in all directions relative'to thecase and will provide shock absorption during all'such movements in view of the inherent dampingcharacteristics of-the material of which the springs I5 are constructed. Under'deflections in an axial direction, the springs I5 will allow a relatively long deflection which will prevent or minimize the transmission of any shocks from the case II. to the instrument '31 itself. Under deflections in a lateral direction, as the'outer'turns of the-volute springs I5 make contact with each other, the resistance to further deflection'b'ecomes progressively greater so as to bring the deflection to a stop with little, if any, ar tothe' instru'ment 31. Although the structure described is'preferably to be so proportioned that all shocks and vibrations which may be sustained"will be isolated from the instrument without the'snubber plates 4| ev'er undergoing sufficient deflection to -make contact with the snubber pads '45, nevertheless it is advisable to include said plates and pads'to receive and break any abnormal shocks which may occur, as where the entire assembly" were accidentally dropped. r

By positioning 'the' center'of "gravity of the suspension in the same plane as the midpoints of all of the springs I5 any tendency to rock or pendulum is avoided ana' aiso the spring suspension and. shock absorbing qualities areefiective in all directions" no matter to what position the case I I may be turned 'during'transit'orwhen installed for use. 1

A modified form of the present invention'is illustrated in Figure 3. Said'modiflcation is similar to the form already described exce t that each of the rods 21 is providediwith two spaced shock absorbers I3 for a total 'o'ffei'ght of such absorbers. The instrument (not shown) carried by said shock mounting s'ystmfmaytheh be fastened to and sustained by tworig'id'rectangular frames 41, as which are secured toe'ach 'of the four rods 21 intermediate'the two springs I5 on said rod. The eight springs 15 insu'ch modified form of the invention should bearr'an'g'ed so thattheir 'midpoints are disposed in "two "s'p'a'cedparallel planes and the instrument sustained by the. frames 41, 49 should be positioned -'so"that'" its center of gravity is in a planeni'idway between the said two planes. The 'opratio'no'fthismodi fied form is similar to that of the first form."

I While there have-been d'es'c'ribedwhat a're at invention, and it is, therefore, aimed in the appended claims, to cover all suchchanges and modifications as 'fall within the true spirit and scope of the invention.

What is claimed is: 7 1. In a shock mount for a load, a volute spring made up, of a coil of flat springy material, a tubu- .lar housing secured to the outer turn of said spring, a rod extending through the axis of said spring and secured to its innermostturn, means secured to 1 the rod 'ito sustain the load with its center of gravity substantially at the midpoint of the spring.

am a means to shock mount a load, at least mutually parallel and their midpoints substantially in a plane'normal to said axes, each spring made up of fiatspringy material coiled intoa Y framework secured tosaid rods an'd'a'daptedto sustain a load with its center jofgraVity: substantially in the plane aforementioned which extends through the midpointsaofthe springs}. 3. In a means to shock-niount a load,; at least three spaced parallel rods,pa spring coiled about each of said rods with its'innermost layersecured to the rod about which it is coiled, the midpoints ofall-of said springs being in a single plane nor-1' mal to said rods, each of. saidisprings'made up of a fiat springy material coiled vinto a volute configuration, a secondsirnilar spring-coiled about each of said rodsn'with its innermost layer-secured to the rod about which it'iscoi1ed,=the1midpoints of said last mentioned springs'beihgin a second single plane'normal to*said rods'andparall'el to and spaced from said first mentionedmlanepa housing assembly secured "to the outermost layers of all of said springs, a framework'secured to all of, said rods and "adapted tosustalna; load with its center. of gravity substantially midway'between the two planes aforesaid. i a 4. In a means to shbckin'ount asload, a :rod, two springs coiled about said-rod withtheininnermost layers secured to said rod-Kat points spaced from-each other, eachof'saidsprings being made up of a flat springymaterial coiled into a volute configuration; a housing'assemblysecured to the" outermost layer 'of said springs, loadsustaining means'secured to'sa'id rod'and'zcapable of sustaining a load with'its center of gravity substantially midway between the midpoints' :of said 'springs- 5. Ina shock mount, a springmade aupof a flat ribbon of springy 'ma'terial coiled into volute configuration, 'a spring housing about said spring,

said housing including atubularsleevesnugly encircling the outer turn of'said spring and two rings securedto said sleeve'an'd extending inwardly therefrom beyond at least part of said outer turn, a rod extending through 'theaxis 'of Y and two rings secured -to saidsleeveand extend ing inwardly therefrom beyond at least part of UNITED STATES PATENTS said outer turn, the inner marginal edge of each of said rings crossing the edge of the adjacent umber Name Date turn of the spring substantially at an oblique ,795,313 Nies Mar. 10, 1931 angle, 5 2,397,804 Nakken et a1 Apr. 2, 1946 QUENTIN FRAZIER.

REFERENCES CITED The following references are of record. in the o file of this patent: 1 

